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given the curve y= x³- 6x²find the coordinates of the stationary points and determine whether each one is a maximum or a minimum​

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Final answer:

To find the stationary points of the curve y=x³-6x², we first determine the first derivative and set it to zero, finding that x=0 and x=4. Substituting these into the original function, we get stationary points (0,0) and (4,-32). Using the second derivative, we determine that (0,0) is a relative maximum and (4,-32) is a relative minimum.

Step-by-step explanation:

To find the coordinates of the stationary points of the curve y= x³- 6x², we first need to find the derivative of the function, which represents the slope of the tangent to the curve at any point. If the slope is zero, we have a stationary point.

Finding the First Derivative

The first derivative of the function is:

y' = 3x² - 12x

To find the stationary points, set the first derivative to zero:

3x² - 12x = 0

x(3x - 12) = 0

Therefore, x = 0 or x = 4.

Stationary Points

Substitute these values into the original function to find the y-coordinates:

For x = 0, y = 0

For x = 4, y = 4³ - 6(4²) = 64 - 96 = -32

The stationary points are (0,0) and (4,-32).

Determining Maximum or Minimum

To determine whether these points are maxima or minima, we take the second derivative:

y'' = 6x - 12

For x = 0: y'' = 6(0) - 12 = -12, which is negative, indicating a relative maximum.

For x = 4: y'' = 6(4) - 12 = 24 - 12= 12, which is positive, indicating a relative minimum.

User Jim Marquardt
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